Charly's Column – f.lux

You don't have to be a vampire to be sensitive to bright light at night. Charly, who – as regular readers know – is a practicing light conservationist, now makes it clear to his desktop PC that it's not good to be too dazzling at night.

If you ask me, it has to be possible to adjust lighting to suit your needs in an unobtrusive and fully automated way. I enabled night mode on my Android smartphone. In the evening, the display shows an ever-decreasing amount of blue light as time progresses. At first, this seems a bit strange and takes getting used to, but it is very friendly on the eyes. Without night mode, I get dazzled when I unlock the phone. This is because its display – like most monitors – is adjusted to a color temperature of 6500 Kelvin.

Cirque du Soleil

Light with a temperature of 6500 Kelvin has a higher blue component than sunlight, which does not exceed 5800 Kelvin even on a clear day. For work during the day in a bright room, 6500 Kelvin is completely OK. In the evening with dim light, I feel as if my PC displays are so bright that work becomes tiring. Of course, I could manually adjust the brightness and color temperature using the buttons on my displays – but that is something that I want to be done automatically. My choice of dimmer goes by the name of f.lux.

Installing f.lux

F.lux is simply pronounced "flux". It is available as a command-line tool [1] or with a GUI [2]. I decided to go for the graphical variant. F.lux is written in Python 3, which means quickly installing some packages on my Ubuntu test system for it to run: